A data processing device includes an internal volume for housing devices and an isolation test system. The isolation test system makes a determination that an electromagnetic interference suppression state of the data processing device is to be determined; in response to the determination: suppresses generation of electromagnetic radiation by the devices; while the generation of the electromagnetic radiation by the devices is suppressed: identifies a quantity of second electromagnetic radiation that propagated through a boundary of the internal volume; makes a second determination, based at least in part on the quantity, that the electromagnetic interference suppression state of the data processing device is an electromagnetic interference suppression compromised state; and initiates performance of an action set to remediate the electromagnetic interference suppression compromised state of the data processing device based on the second determination.